The Effects of Carbon Dioxide on Coral Reefs – Charlotte Westwater and Becky Engeleiter
In this lab, a marine environment was simulated using coral and synthetic seawater in order to test carbon dioxide’s indirect effect on ocean coral. Carbon dioxide emissions are created by the burning of fossil fuels for energy. One third of these emissions are absorbed by oceans, where they react with water molecules to create carbonic acid. This acid lowers the pH level of ocean water, eroding carbonate minerals that make up the exoskeleton of coral. In the lab set-up, two pieces of coral differing in size were exposed to carbon dioxide at two different flow rates. The sample at the lower flow rate (0.06 L/min) lost 1.5% of its mass, while the sample at the higher flow rate (0.10 L/min) lost 1.8% of its mass. The controlled sample, which was not exposed to carbon dioxide, lost 0.20% of its mass. These results support the initial hypothesis that the greater the amount of carbon dioxide introduced into seawater, the more erosion of coral structure, due to acidification, will take place. Error in this lab could have been reduced by better regulating the initial pH levels of the seawater samples, as well as controlling the flow of carbon dioxide into each bottle.
Bibby R, Cleall-Harding P, Rundle S, Widdicombe S, Spicer J. Ocean Acidification Disrupts Induced Defenses in the Intertidal Gastropod Littorina Littorea [Internet]. PubMed Central Journals; 2007 [cited 8 Mar 2010]. 6 p. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2391239/ Pala C. The Pacific Ocean’s Acidification Laboratory [Internet]. Environmental Science & Technology; 2009 [cited Mar 10 2010]. 3 p. Available from: http://pubs.acs.org/doi/abs/10.1021/es902148f
In this lab, a marine environment was simulated using coral and synthetic seawater in order to test carbon dioxide’s indirect effect on ocean coral. Carbon dioxide emissions are created by the burning of fossil fuels for energy. One third of these emissions are absorbed by oceans, where they react with water molecules to create carbonic acid. This acid lowers the pH level of ocean water, eroding carbonate minerals that make up the exoskeleton of coral. In the lab set-up, two pieces of coral differing in size were exposed to carbon dioxide at two different flow rates. The sample at the lower flow rate (0.06 L/min) lost 1.5% of its mass, while the sample at the higher flow rate (0.10 L/min) lost 1.8% of its mass. The controlled sample, which was not exposed to carbon dioxide, lost 0.20% of its mass. These results support the initial hypothesis that the greater the amount of carbon dioxide introduced into seawater, the more erosion of coral structure, due to acidification, will take place. Error in this lab could have been reduced by better regulating the initial pH levels of the seawater samples, as well as controlling the flow of carbon dioxide into each bottle.
Keywords: ocean acidification, flow rate, carbon dioxide emissions, pH level, acidic, basic, distilled water, coral, incubator, carbonic acid, carbonate minerals, exoskeleton, synthetic seawater, pH sensor
Bibby R, Cleall-Harding P, Rundle S, Widdicombe S, Spicer J. Ocean Acidification Disrupts Induced Defenses in the Intertidal Gastropod Littorina Littorea [Internet]. PubMed Central Journals; 2007 [cited 8 Mar 2010]. 6 p. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2391239/
Pala C. The Pacific Ocean’s Acidification Laboratory [Internet]. Environmental Science & Technology; 2009 [cited Mar 10 2010]. 3 p. Available from: http://pubs.acs.org/doi/abs/10.1021/es902148f